TY  - JOUR
AU  - Stellin, Gianluca
AU  - Meißner, Ulf-G.
TI  - P-wave two-particle bound and scattering states in a finite volume including QED
JO  - The European physical journal / A
VL  - 57
IS  - 1
SN  - 1434-601X
CY  - Heidelberg
PB  - Springer
M1  - FZJ-2021-01128
SP  - 26
PY  - 2021
AB  - The mass shifts for two-fermion bound and scattering P-wave states subject to the long-range interactions due to QED in the non-relativistic regime are derived. Introducing a short range force coupling the spinless fermions to one unit of angular momentum in the framework of pionless EFT, we first calculate both perturbatively and non-perturbatively the Coulomb corrections to fermion-fermion scattering in the continuum and infinite volume context. Motivated by the research on particle-antiparticle bound states, we extend the results to fermions of identical mass and opposite charge. Second, we transpose the system onto a cubic lattice with periodic boundary conditions and we calculate the finite volume corrections to the energy of the lowest bound and unbound $T^±_1$ eigenstates. In particular, power law corrections proportional to the fine structure constant and resembling the recent results for S-wave states are found. Higher order contributions in $α$ are neglected, since the gapped nature of the momentum operator in the lattice environnement allows for a perturbative treatment of the QED interactions.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000610440300001
DO  - DOI:10.1140/epja/s10050-020-00319-1
UR  - https://juser.fz-juelich.de/record/890686
ER  -